Formation
of the Solar System – We have to explain formation and composition of
the Sun, the planets, and the configuration of the Solar System.

Sun
forms by gravitational collapse

Planets
form out of left over gas and dust, terrestrial planets close in since the
temperature in the Solar nebula is higher near the center, and condensation
of lighter elements is high.Gases
get pushed out early, heavier elements condense into solids and remain in
the inner regions – form terrestrial planets.

Conservation
of Angular Momentum specifies that the all of the planets should be
rotating in the same direction and spinning in the same direction as the
Sun rotates.

Inner
planets form by accretion, outer planets form by accretion and
capture of gas.

·Mountains – mountains formed by impacts of
asteroids and meteors, not geologic processes.

·Far side – almost all cratered Terrae, only one
small Maria!

Structure
of the Moon –

·No current magnetic field – possibly has a small
iron-rich core, but cooled long ago.

·Near-side crust is much thinner than the far-side
crust, near side ~ 60 km, far side ~ 100 km. Explains absence of Maria on far
side!

·Solid mantle ~ 800 km thick

·Core less than 700 km thick.

·Lunar surface covered with pulverized rocks (regolith),
but since no atmosphere or water > No Weathering!Craters remain undisturbed over geologic ages.

7.Lunar exploration –

·Un-manned landings –Surveyors (USA) – took pictures

·Apollo Lunar Missions –(don’t memorize this for the test, just wanted you to have
this info!!!)

Apollo 11 landed July 20, 1969
in Mare Tranquillitatis

Apollo 12 landed Nov. 19, 1969 in Oceanus Procellarum

Apollo 13 didn’t land (see tom Hanks movie!!)

Apollo 14 landed Jan. 31, 1971 in a
crater named Fra Mauro

Apollo 15 landed July 30, 1971 in a
ridge called Hadley-Apennines

Apollo 16 landed April 21, 1972 in
Crater Descartes

Apollo 17 landed Dec. 11, 1972 in Maria
Taurus-Littrow valley.

8.Lunar Rocks –

·Formed 3 to 4.5 billion years ago

·No sedimentary rocks, no true metamorphic rocks, all
igneous

·Some rocks modified by meteor impacts!

·Maria – basalt rock, highlands or Terrae – anorthosite

9.Lunar formation –

·Moon formed as a result of the collision of a
Mars-sized object with the Earth.The
Earth was liquefied, and part of the Earth and part of the projectile was
ejected, and reformed together to form the Moon.This occurred very early in the history of the solar system,
within first 0.1 billion years

7.Pictures revealed “Scarps”, Wrinkling of crust due to
the fact it cooled and solidified before the core did.Subsequent core contraction caused the
surface to break and fold creating steep cliffs we call scarps.

8.Also showed Caloris Basin (an impact crater) and diametrically
opposite (on the other side of the planet) the Marius Hills, caused by
convergence of seismic waves from the Caloris Impact!